Thevenin-based Battery Model with Ageing Effects in Modelica

In the era of transition to the renewable energy the importance of a good model of the battery cannot be overrated. This paper presents the Thevenin-based battery model with aging effects that is parameterized and validated with respect to the battery manufacturer's datasheets. The proposed model of the battery combines the Thevenin-based and runtime-based battery models that represent charging/discharging transient behavior of the battery. The model has been further improved by adding ageing effects using crack propagation model. Charging rate, depth of discharge and overcharge were used as main factors for capacity fading, while temperature effects were neglected as the temperature is not controllable parameter in the application the model is designed for. This allows to speed up the simulation getting an acceptable performance of a model-based optimization such as model predictive control or machine learning. The developed model was implemented using Modelica language, allowing to simulate the model in any software that supports Functional-Mockup Interface.